Hezekiah wanted a sign to prove his healing, which makes sense. He went from having a terminal illness to being promised fifteen more years of life. God sometimes gave signs as visible symbols of his plans (see also 2 Kings 19:29; Genesis 9:12–17; Exodus 4:1–9; 12:12–13; 31:12–13, 17; 1 Kings 13:1–3).